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  1. <meta charset="utf-8" lang="en"><style class="fallback">body{visibility:hidden;}</style>
  2. # Overview
  3. This repository includes a number of example scenes and
  4. data for use with the [pbrt-v3]( renderer,
  5. which corresponds to the system described in the third edition of
  6. _Physically Based Rendering_, by Matt Pharr, Wenzel Jakob, and Greg
  7. Humphreys. (See also the [pbrt website](
  8. We hope that this data will be useful to users of `pbrt`, developers making
  9. changes to the system, and researchers in rendering. To our knowledge, all
  10. of these scenes and data can be used fairly freely. Some data is licensed
  11. under a Creative Commons Attribution license; see details in
  12. Section [Scene Credits] of this document.
  13. # Data Sets
  14. In addition to example scenes, there is some useful data for use with the
  15. system.
  16. * [bsdfs/](bsdfs/): this directory includes a variety of bidirectional scattering
  17. distribution functions (BSDFs) for use with the `FourierMaterial`. See, for
  18. example, the [coffee-splash](coffee-splash) scene for use of such a BSDF in a scene.
  19. * New versions of BSDFs for use with `FourierMaterial` can be generated
  20. with [layerlab](
  21. * [lenses/](lenses/): lens description files for a handful of real-world lens
  22. systems, for use with the `RealisticCamera`. See the scenes
  23. [villa/villa-photons.pbrt](villa/villa-photons.pbrt) and
  24. [sanmiguel/f6-17.pbrt](sanmiguel/f6-17.pbrt) for examples of their use.
  25. * [spds/](spds/): measured spectral power distributions for a variety of standard
  26. illuminants, light sources, metals, and the squares of the Macbeth color
  27. checker.
  28. # Scenes
  29. A variety of scenes are available, ranging from simple ones that show off
  30. an individual feature of the system, to more interesting ones that
  31. demonstrate complex lighting effects in scenes with detailed geometry and
  32. realistic reflection models.
  33. Scene files for many of the rendered figures in the book are included here;
  34. for example, [dragon/f11-13.pbrt](dragon/f11-13.pbrt) corresponds to Figure
  35. 11.13 in the third edition of the book.
  36. ## Directory Organization
  37. We've tried to organize all of the scene directories in a consistent
  38. manner; each scene directory is self-contained, containing all of the
  39. geometry, textures, and additional data needed to render the scene.
  40. With a few exceptions, each `*.pbrt` file in a scene directory represents a
  41. separate variant of the scene to be rendered (possibly with different light
  42. source configurations, different camera positions, etc.) Some scenes have
  43. `geometry.pbrt`, `lights-*.pbrt` and `materials.pbrt` files that collect
  44. common geometry and material definitions across these variants. Thus, you
  45. should be able to just run `pbrt scene-name.pbrt` for any of the remaining
  46. `*.pbrt` files to render the corresponding scene.
  47. Complex triangle meshes and other complex geometry is stored in the
  48. `geometry/` directories and texture maps are all in the respective
  49. `textures/` directories. (Similarly, any SPDs, realistic camera lenses,
  50. or BSDF files are stored in corresponding sub-directories.)
  51. The [images/](images/) directory (which has a structure that parallels that
  52. of the scene directories) has EXR and PNG files corresponding to the final
  53. output from rendering each corresponding scene. All PNGs were generated
  54. using the `imgtool` program from the `pbrt-v3` distribution; many had a
  55. scale factor applied with the `--scale` command-line option, and a number
  56. include a bit of bloom to improve visual realism (via the `--bloomlevel`
  57. and related command-line options.) Sometimes the corresponding `*.pbrt`
  58. file has a comment under the `Film` directive with the command line options
  59. that were used for `imgtool`.
  60. ## A note about clamped sample values
  61. Some of these scenes have very difficult-to-sample light transport paths
  62. that in turn cause high variance, which manifests itself as scattered very
  63. bright pixels in images (often called "fireflies"). (For example, scenes
  64. with bumpy specular surfaces that are illuminated by realistic sky environment
  65. maps suffer from this issue when a path intersects the specular surface and
  66. is then scattered such that it happens to intersect the sun.)
  67. There is an option for pbrt's Film implementation that allows the user to
  68. specify a maximum value for the luminance of any sample added to the film;
  69. if enabled, any sample with a larger luminance has its luminance scaled
  70. down so that it is equal to the maximum. In turn, the impact of fireflies
  71. in images can be greatly reduced.
  72. We have used this option for a number of challenging scenes in the
  73. following. As such, **bias has been introduced into the the images that
  74. pbrt generates for those scenes**. We highlight this issue for two reasons:
  75. first, if you want to use those scenes as unbiased comparisons to another
  76. rendering system or to your implementation of a new light transport
  77. algorithm, it's important to be aware of this (and likely, to modify the
  78. scene files to disable this setting). Second, if you're developing a new
  79. light transport algorithm, these scenes provide a number of challenging
  80. situations that current algorithms don't handle well; new algorithms that
  81. handle them effectively would be useful contributions to rendering.
  82. ## Overview of Scenes
  83. ![Barcelona Pavilion day](images/barcelona-pavilion/pavilion-day.png height="200px")
  84. ![Barcelona Pavilion night](images/barcelona-pavilion/pavilion-night.png height="200px")
  85. [barcelona-pavilion](barcelona-pavilion): Model of van der Rohe's classic
  86. [Barcelona Pavilion](,
  87. including both daytime and nighttime lighting setups. In the daytime setup,
  88. all illumination comes from a realistic sky model encoded in an HDR
  89. environment map. The night model has a very dark sky map and a number of
  90. area light sources; it is particularly challenging to render, as much of
  91. the illumination travels through one or more layers of glass before hitting
  92. a surface.
  93. ![](images/bathroom/bathroom.png height="200px")
  94. [bathroom](bathroom): Modern bathroom with soft indirect lighting and
  95. depth of field. Given the mirrors and bright wight walls, multi-bounce
  96. indirect illumination has a substantial effect on the overall appearance
  97. of the scene.
  98. ![](images/bmw-m6/bmw-m6.png height="200px")
  99. [bmw-m6](bmw-m6): BMW M6 car (model year 2006) illuminated by a realistic
  100. skylight model.
  101. ![](images/breakfast/breakfast-lamps.png height="200px")
  102. [breakfast](breakfast): Indoor scene with chairs around a table. One
  103. variant of the scene has light streaming in through blinds from the side
  104. such that most of the scene is only illuminated indirectly; finding these
  105. indirect illumination paths can be challenging. Another variant is only
  106. illuminated by the lights above the table; handling the resulting light
  107. transport through the glass light fixtures is a good challenge for many
  108. light transport algorithms.
  109. ![](images/buddha-fractal/buddha-fractal.png height="200px")
  110. [buddha-fractal](buddha-fractal): Stanford Buddha model made out of Stanford Buddha
  111. models. 25,250 instances, each with 29,890 triangles, giving a total
  112. geometric complexity of over 750 million triangles.
  113. ![](images/bunny-fur/f3-15.png height="200px")
  114. [bunny-fur](bunny-fur): Stanford Bunny with fur growing out of it, modeled using the
  115. new curve shape added to `pbrt` in the third edition of the book. Over
  116. 1.5 million curves are used.
  117. ![](images/caustic-glass/f16-9c.png height="200px")
  118. [caustic-glass](caustic-glass): A delightfully complex caustic pattern that
  119. results from light being projected through a realistic model of a bumpy
  120. glass.
  121. ![](images/chopper-titan/chopper-titan.png height="200px")
  122. [chopper-titan](chopper-titan): Shiny motorcycle sitting on a glossy
  123. surface, illuminated by a sunset.
  124. ![White cloud](images/cloud/cloud.png height="200px")
  125. ![Smoky cloud](images/cloud/smoke.png height="200px")
  126. [cloud](cloud): One scene with a bright white cloud, showing the effect of
  127. multiple scattering in participating media, and another, with the same
  128. volume density but with much more absorption, leading to a much darker
  129. cloud. The two images show the difference between highly-scattering and
  130. highly-absorptive media.
  131. ![](images/coffee-splash/splash.png height="200px")
  132. [coffee-splash](coffee-splash): A splash of coffee in a cup with a spoon,
  133. rendered using a complex simulated BRDF for the cup and saucer, and
  134. multiple scattering in participating media inside the splash.
  135. ![](images/contemporary-bathroom/contemporary-bathroom.png height="200px")
  136. [contemporary-bathroom](contemporary-bathroom): Another contemporary
  137. bathroom scene. This scene is quite challenging to render without visible
  138. noise: specular light transport by the large mirror and the
  139. very small area light sources surrounded by glass in the light bulbs are
  140. difficult to render efficiently.
  141. ![](images/crown/crown.png height="200px")
  142. [crown](crown): Detailed model of the Austrian Imperial Crown, featuring an
  143. accurate reflection model for the gold metal surfaces, and many gems that
  144. refract light passing through them.
  145. ![](images/dragon/f9-3.png height="200px")
  146. [dragon](dragon): A scanned dragon model rendered with many different materials,
  147. showing off the visual differences between them.
  148. ![](images/ecosys/ecosys.png height="200px")
  149. [ecosys](ecosys): Fairly complex outdoor scene with many plants and trees,
  150. illuminated by an environment map. This scene was used for the cover image
  151. for the first edition of _Physically Based Rendering_.
  152. [figures](figures): A variety of fairly simple scenes used for figures in the book.
  153. ![](images/ganesha/ganesha.png height="200px")
  154. [ganesha](ganesha): Very detailed scan of a small statue with over 4.3
  155. million triangles, illuminated by a few area light sources.
  156. ![](images/head/head.png height="200px")
  157. [head](head): Human head model with a realistic BSSRDF, showing the effect of
  158. subsurface scattering.
  159. ![](images/killeroos/killeroo-gold.png height="200px")
  160. [killeroos](killeroos): The classic "killeroo" model, in a variety of settings.
  161. ![view-0](images/landscape/view-0.png height="200px")
  162. ![view-1](images/landscape/view-1.png height="200px")
  163. ![view-2](images/landscape/view-2.png height="200px")
  164. ![view-3](images/landscape/view-3.png height="200px")
  165. [landscape](landscape): Very complex realistic outdoor landscape scene,
  166. featuring 23,241 unique plant models. Thanks to object instancing, the
  167. scene has a total geometric complexity of 3.1 billion triangles, even
  168. though only 24 million triangles need to be stored in memory. `view-0.pbrt`
  169. is the cover image of the third edition of the _Physically Based Rendering_
  170. book.
  171. ![](images/pbrt-book/book.png height="200px")
  172. [pbrt-book](pbrt-book): A realistic model of the second edition of the _Physically
  173. Based Rendering_ book.
  174. ![](images/sanmiguel/sanmiguel.png height="200px")
  175. [sanmiguel](sanmiguel): A complex model inspired by a hotel in San Miguel de
  176. Allende, Mexico.
  177. ![anim-bluespheres.pbrt](images/simple/anim-bluespheres.png height="200px")
  178. [simple](simple): A variety of relatively simple scenes.
  179. ![](images/sportscar/sportscar.png height="200px")
  180. [sportscar](sportscar): Sportscar model, in a variety of illumination settings,
  181. showing off the substantial differences in overall visual appearance that
  182. result.
  183. ![](images/sssdragon/dragon_10.png height="200px")
  184. [sssdragon](sssdragon): Dragon model rendered with subsurface scattering,
  185. where multiple scene description files show the visual effect of changing
  186. the density of the scattering medium.
  187. ![](images/structuresynth/arcsphere.png height="200px")
  188. [structuresynth](structuresynth): A few interesting procedural scenes scenes converted
  189. from [Structure Synth]( into
  190. `pbrt`'s format.
  191. ![](images/tt/tt.png height="200px")
  192. [tt](tt): Audi TT car model.
  193. ![](images/veach-bidir/bidir.png height="200px")
  194. [veach-bidir](veach-bidir): A version of a classic scene with a variety of complex
  195. types of light transport developed by Eric Veach to show the value of
  196. bidirectional path tracing.
  197. ![](images/veach-mis/f14-13-mi.png height="200px")
  198. [veach-mis](veach-mis): Another scene based on one by Eric Veach, this one showing
  199. off the benefit of multiple importance sampling when rendering surfaces
  200. of varying glossiness illuminated by light sources of various sizes.
  201. ![](images/villa/villa-daylight.png height="200px")
  202. [villa](villa): Modern indoor environment. The `villa-daylight.pbrt` version is
  203. particularly tricky to render, as all of the indoor lighting comes via
  204. specular paths from the outside through the windows.
  205. ![](images/vw-van/vw-van.png height="200px")
  206. [vw-van](vw-van): Volkswagen Van, illuminated by a HDR environment map.
  207. ![](images/volume-caustic/caustic.png height="200px")
  208. [volume-caustic](volume-caustic): A glass sphere in participating media, showing off a
  209. volumetric caustic--light being focused in the scattering medium after
  210. passing through the sphere.
  211. ![Whiteroom daytime](images/white-room/whiteroom-daytime.png height="200px")
  212. ![Whiteroom night](images/white-room/whiteroom-night.png height="200px")
  213. [white-room](white-room): Interior scene, with two illumination
  214. configurations. The daytime variant is primarily illuminated by light
  215. coming through the windows from the outdoors, while the nighttime version
  216. is illuminated by the two lights in the scene.
  217. ![](images/yeahright/yeahright.png height="200px")
  218. [yeahright](yeahright): An unusual and intricate form on a glossy plate.
  219. [wip](wip): This directory has a few scenes that aren't quite ready;
  220. renderings don't yet look great, parameters need tuning, etc. We'll try
  221. to get to this eventually, or if you're able to get them in good shape,
  222. please submit an update (see the following).
  223. # Converting Scenes to pbrt's Format
  224. Given an amazing scene in another 3D file format, there are a few
  225. options for converting it to be used in pbrt. (We're always happy to have
  226. help with improvements in this area!)
  227. ## Cinema 4D
  228. The `exporters/cinema4d` directory in the pbrt-v3 distribution provides an
  229. exporter from Cinema 4D. This exporter was developed to export the amazing
  230. "landscape" scene that is on the book's front cover from Cinema 4D, so thus
  231. is up to date with respect to pbrt's material models and rendering
  232. settings. We have seen good results with using this exporter for other
  233. Cinema 4D scenes.
  234. ## Wavefront OBJ
  235. The pbrt-v3 distribution includes a converter from the Wavefront OBJ
  236. format, `obj2pbrt`, that is built when the rest of the system is compiled.
  237. To run it, provide the path to an OBJ file and a filename for a new pbrt
  238. file:
  239. ```bash
  240. $ obj2pbrt scene.obj scene.pbrt
  241. ```
  242. If there is an accompanying material description file (e.g. `scene.mtl`),
  243. the values in it will be roughly mapped to corresponding pbrt materials.
  244. You will likely need to manually edit and tune the materials in the
  245. generated pbrt file in order to achieve reasonably good-looking
  246. results.
  247. Note that OBJ files only describe scene geometry; they don't include camera
  248. specifications or descriptions of light sources. (Thus, the generated pbrt
  249. input file only includes shape and material specifications that you'll need
  250. to add inside the `WorldBegin`/`WorldEnd` block of a full pbrt input file.)
  251. Unless you have camera and light source information separately, you'll need
  252. to specify both on your own (see "General Tips" below for some ideas about
  253. how to do this.)
  254. ## Blender
  255. Many very nice scenes have been modeled in
  256. [Blender]( and are freely available. (See, for
  257. example, the [BlendSwap]( website for many
  258. scenes that can be used via a Creative Commons license.) Our experience has
  259. been that the best approach to export scenes from Blender is to use
  260. Blender's native OBJ export (available via the File/Export menu item) and
  261. then to use the obj2pbrt utility described above to convert to pbrt's
  262. format.
  263. Blender scene files may have texture maps for the scene included directly
  264. in their `.blend` file. Choose "File/External Data/Unpack into Files" in
  265. Blender to save those files independently on disk. (Note that if the
  266. textures aren't PNG or TGA format, you'll need to convert to one of those
  267. for pbrt to be able to use them.)
  268. We would have hoped that the Blender exporter for
  269. [LuxRender]( would have worked well for pbrt
  270. (LuxRender is originally based on pbrt and still has a similar input file
  271. format.) Unfortunately, our experience has been that exporting to OBJ and
  272. using obj2pbrt gives a better starting point for the scene
  273. materials. (Further, the LuxRender Blender exporter silently fails if there
  274. aren't any lights in the scene.) We suspect that using this exporter as a
  275. starting point for a new direct Blender to pbrt exporter might be a
  276. worthwhile approach.
  277. ## Old Exporters
  278. The pbrt-v2 distribution includes
  279. [exporters]( for 2010
  280. era 3DS Max (which was used for the model used for the cover image for the
  281. second edition of the book), Blender, Mathematica, and [Structure
  282. Synth]( All of these are very much
  283. out of date, both due to changes over the past six years in in the systems
  284. they exported from as well as changes in pbrt. Some of these may be useful
  285. for developing updated exporters for the corresponding systems for pbrt-v3.
  286. ## General Tips
  287. A scene exported using one of the above exporters is certain to not
  288. immediately render beautifully as is. Here are some suggestions for how to
  289. take an initial export and turn it into something that looks great.
  290. First, you may find it useful to run
  291. ```bash
  292. $ pbrt --toply scene.pbrt > newscene.pbrt
  293. ```
  294. This will convert triangle meshes into more compact binary PLY files,
  295. giving you a much smaller pbrt scene file to edit.
  296. Next, if the exporter doesn't include camera information, the first thing
  297. to do is to find a good view. The "environment" camera (which renders an
  298. image in all directions) can be useful for finding a good initial position
  299. for the camera. Keep rendering images and adjusting the camera position to
  300. taste. (For efficiency, use as few pixel samples as you can tolerate and
  301. learn to squint and interpret noisy renderings!) Then, you can use the
  302. origin you've chosen as the basis for specifying a `LookAt` transformation
  303. for a more conventional camera model.
  304. While placing the camera, it can be helpful to have a point light source at
  305. the camera's position. Adding a light source like the following to your
  306. scene file does this in a way that ensures that the light moves
  307. appropriately to wherever the camera has been placed. (You may need to
  308. scale the intensity up or down for good results--remember the
  309. radius-squared falloff!
  310. ```
  311. AttributeBegin
  312. CoordSysTransform "camera"
  313. LightSource "point" "color I" [10 10 10]
  314. AttributeEnd
  315. ```
  316. Once the camera is placed, we have found that it's next useful to set up
  317. approximate light sources. For outdoor scenes, a good HDR environment map
  318. is often all that is needed for lighting. (You may want to consider using
  319. `imgtool makesky` to make a realistic HDR sky environment map.)
  320. For indoor scenes, you may want a combination of an environment map for the
  321. outside and point and/or area light sources for interior lights. You may
  322. find it useful to examine the scene in the modeling system that it came
  323. from to determine which geometry corresponds to area light sources and to
  324. try adding `AreaLightSource` properties to those. (Note that in pbrt, area
  325. light sources only emit lights on the side that the surface normal points;
  326. you may need a `ReverseOrientation` directive to make the light come out in
  327. the right direction.)
  328. Given good lighting, the next step is to tune the materials (or set them
  329. from scratch). It can be helpful to pick a material and set it to an
  330. extreme value (such as a "matte" material that is pure red) and render the
  331. scene; this quickly shows which geometric models have that material
  332. associated with it. Alternatively, consider applying this
  333. [patch](html/mtl.patch.txt) to your pbrt source tree; after rebuilding
  334. pbrt, if you set the `PBRT_MTL_HACK` environment variable and render the
  335. scene, pbrt will generate a separate image for each `NamedMaterial`
  336. in the scene, with a filename corresponding to the material name. Each
  337. of these images will only include the objects with that material, which
  338. makes it easier to see what's what.
  339. As you figure out which material names correspond to what geometry, watch
  340. for objects that are missing texture maps and add `Texture` specifications
  341. for them and use them in the materials. (The good news is that such objects
  342. generally do have correct texture coordinates with them, so this mostly
  343. just works.)
  344. # Submitting Updates
  345. We'd love to increase the scope (and quality) of scenes available for use
  346. with `pbrt`. If you have a nice scene in `pbrt`'s format that you'd like to
  347. have included in this distribution, or if you have improvements to the
  348. current set of scenes, we'd love to have them! (Even finding additional
  349. good camera locations for the existing scenes or generating variants of
  350. some of the existing scenes with different lighting setups is helpful.)
  351. We're particularly interested in adding scenes that include complex and
  352. realistic character models as well as scenes with realistic distributions
  353. of hair or fur.
  354. Unfortunately, it's not possible to host large binary distributions on
  355. github, so submitting scene updates a little more involved than sending a
  356. pull request. There are a few options.
  357. * For changes small enough to be sent via email, you can use
  358. `git format-patch` to make a patch that we can apply and push to the
  359. repository. (Send the patch to
  360. * For larger changes, consider the `git bundle` command to generate a
  361. binary representation of the changes. Post the resulting file online
  362. somewhere that we can access it, send us a pointer (again,
  363., and we'll merge it.
  364. * Finally, if you're not comfortable enough with git for those options,
  365. feel free to create a zip or tar file with a new scene and send us a
  366. pointer to it; we can take it from there.
  367. # Scene Credits
  368. * barcelona-pavilion: Thanks to [Hamza Cheggour](,
  369. who created this [great
  370. model](
  371. and made it available via a CC-BY license.
  372. * bathroom: Thanks to "nacimus", CC-BY license. Downloaded from
  373. [Blendswap](
  374. * bmw-m6: Thanks to Fred C. M'ule Jr. ("tyrant monkey" on BlendSwap) for
  375. this nice car model. CC-Zero (public domain) license. Downloaded from
  376. [Blendswap](
  377. * breakfast: Thanks to "Wig42", CC-BY license. Downloaded from
  378. [Blendswap](
  379. * buddha-fractal: Thanks for Guillermo M. Leal Llaguno for this fun variant
  380. of the Stanford Buddha model. (Buddha model courtesy [Stanford Computer
  381. Graphics Laboratory](
  382. * bunny-fur: Bunny model courtesy [Stanford Computer Graphics
  383. Laboratory]( Environment map
  384. via, thanks to Bernhard Vogl.
  385. * caustic-glass: Thanks to Simon Wendsche ( for
  386. the model.
  387. * chopper-titan: Thanks to julioras3d for this model; CC-BY
  388. license. Downloaded from
  389. [Blendswap](
  390. * cloud: Smoke dataset courtesy Duc Nguyen and Ron Fedkiw. Skylight
  391. environment map courtesy Nolan Goodnight.
  392. * coffee-splash: Scene thanks to "guismo"; CC-BY license. Downloaded from
  393. [Blendswap]( Environment map
  394. via, thanks to Bernhard Vogl.
  395. * contemporary-bathroom: Scene thanks to
  396. [Mareck](, CC-Zero (public domain)
  397. license. "contemporary_china" texture used for wallpaper thanks to [Adam
  398. Charlts](; texture contrast
  399. was increased for the render. "American_walnut_pxr128" wood texture
  400. courtesy [Pixar Animation
  401. studios](,
  402. CC-BY 4.0 license. Abstract print seen in mirror based on a smoke
  403. photograph by [Vanessa
  404. Pike-Russell](, CC-BY
  405. license; the photo was inverted and contrast was adjusted for rendering.
  406. Hurricane image used for photo on wall courtesy [NASA Goddard Space
  407. Flight Center](, CC-BY license.
  408. * crown: This amazing model was created by Martin Lubich
  409. (
  410. * dragon: Dragon model courtesy Christian Schüller. Environment map via
  411., thanks to Bernhard Vogl.
  412. * ecosys: Scene from Deussen et al., [Realistic modeling and rendering of
  413. plant ecosystems](
  414. * ganesha: Model scanned by Wenzel Jakob.
  415. * head: Model thanks to Infinite Realities, Inc., CC-BY license.
  416. Environment map thanks to [USC-ICT light probe image gallery](
  417. * killeroos: Thanks to [headus]( for the
  418. model.
  419. * landscape: Many thanks to Jan-Walter Schliep, Burak Kahraman, and Timm
  420. Dapper from [Laubwerk]( for this amazing scene.
  421. * pbrt-book: Thanks to Karl Li (yiningkarlli@) for this fun model.
  422. * sanmiguel: Thanks to Guillermo M. Leal Llaguno for this excellent scene.
  423. * sportscar: Excellent model and pbrt conversion courtesy of Yasutoshi
  424. Mori (@MirageYM); CC-BY license. Skylight environment maps courtesy Nolan
  425. Goodnight.
  426. * sssdragon: Dragon model courtesy [Stanford Computer Graphics
  427. Laboratory]( Environment map
  428. via, thanks to Bernhard Vogl.
  429. * structuresynth: Environment map thanks to [USC-ICT light probe image gallery](
  430. * tt: Thanks for Marko Dabrovic and Mihovil Odak for the car model.
  431. Environment map thanks to [USC-ICT light probe image gallery](
  432. * villa: Many thanks to Florent Boyer for this scene. Skylight environment
  433. map courtesy Nolan Goodnight.
  434. * vw-van: Model courtesy of
  435. [Greyscalegorilla](,
  436. exported from Cinema4D using the [Cinema4D pbrt
  437. exporter](
  438. * white-room: Scene thanks to Jay Hardy, CC-BY
  439. license. Downloaded from [Blendswap](
  440. * yeahright: "Interesting" shape generated by Keenan Crane
  441. ( Environment
  442. map thanks to [USC-ICT light probe image
  443. gallery](
  444. <!-- Markdeep: --><style class="fallback">body{visibility:hidden;}</style><script src="html/markdeep.min.js"></script>